Grant Davies, 39, ran a dance studio in Sydney's inner west with his sister, and trained performers for hit productions, including Billy Elliot.

He was charged in May with a string of child sex and pornography offences, and has been in custody ever since.

Those charges related to students at the dance studio who were aged between nine and 14 at the time of the alleged offences, police have said.

On Wednesday, Burwood local court was told that 36 new charges had been filed against Davies.

According to police, the extra charges include 14 counts of aggravated sexual assault, 18 counts of aggravated indecent assault and four counts of aggravated acts of indecency.

In the brief hearing, a lawyer for the crown said there was "significant material" to address in the evidence brief, including photographs, police statements and a 60-page statement from a complainant.

Davies' lawyer did not apply for bail on behalf of the accused and it was formally refused by magistrate Christopher Longley.

Davies was previously refused bail in May after concerns were raised he could try and delete alleged evidence if released.